Preliminary study on the detection efficiency and estimation of minimum detectable activity for a NaI(Tl)-based seawater monitoring system

The aim of this study was to estimate radionuclide levels in breast milk and the transferred dose to their infants in Sendai (100 km from Fukushima), Japan after the 2011 Fukushima nuclear disaster. Radionuclide concentrations were analyzed in 101 specimens of breast milk collected in 2012. Median values for minimum detectable activities were 0.39, 0.34, 1.1, 1.89, and 17.1 Bq/kg for 137Cs, 134Cs, 131I, 110mAg, and 40K, respectively. Only radionuclides from 40K were detected. To estimate potential exposure and radiocesium dose, we assumed that the samples contained each minimum detectable activity level. The mean minimum detectable activity concentrations (standard deviation) of 137Cs and 134Cs were 0.42 (0.15) and 0.37 (0.14) Bq/kg, respectively. Means of estimated dietary intakes of 137Cs and 134Cs among infants were 0.35 (0.12) and 0.31 (0.11) Bq/day, respectively. The committed effective doses of radiocesium in infants aged 3 and 12 months via breastmilk were estimated at 5.6 (2.1) and 3.3 (1.2) μSv/year, respectively. Dietary intakes of 137Cs and 134Cs in breastfeeding mothers were back-calculated at 1.9 (0.71) and 1.7 (0.65) Bq/day, respectively. The study verified no discernible exposure to radionuclides among infants. The most conservative estimates were below the Japanese internal exposure limit of 1 mSv/year.

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176Lu effect on the minimum detectable activity limits for a dual head, LSO: Ce based, PET system

2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC) ◽

10.1109/nssmic.2013.6829191 ◽

2013 ◽

Keyword(s):

Minimum Detectable Activity ◽

Detectable Activity ◽

Pet System

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List mode data acquisition technique for Compton suppression and minimum detectable activity (MDA) reduction in standard high-volume air samples

Radiation Physics and Chemistry ◽

10.1016/j.radphyschem.2022.109964 ◽

2022 ◽

pp. 109964

Author(s):

Mahdi Tourang ◽

Asghar Hadadi ◽

Mitra Athari Allaf ◽

Dariush Sardari

Keyword(s):

Data Acquisition ◽

High Volume ◽

Compton Suppression ◽

Minimum Detectable Activity ◽

List Mode ◽

Air Samples ◽

Detectable Activity ◽

Acquisition Technique

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Minimum Detectable Activity of Pb-210 in Skull From In vivo Measurements: Insights From the Literature

Frontiers in Energy Research ◽

10.3389/fenrg.2021.759850 ◽

2021 ◽

Vol 9 ◽

Author(s):

Xiangpeng Meng ◽

Yuanyuan Liu ◽

Bin Wu ◽

Jianping Cheng ◽

Li Wang ◽

...

Keyword(s):

Limit Of Detection ◽

Minimum Detectable Activity ◽

Active Area ◽

Semiconductor Detectors ◽

Background Count ◽

Radon Exposure ◽

Detectable Activity ◽

Retrospective Assessment ◽

History Of

To address the urgent need for the retrospective assessment of the health conditions of people with a history of appreciable radon exposure, a novel technique that directly measures the characteristic γ-rays emitted from Pb-210 in the living skull was developed. Since the first pioneering study in 1968, this technique has experienced continued advancement over more than half a century, where the limit of detection of Pb-210 is a common criterion to assess the performance of the measuring devices. However, researchers have defined the limit of detection in assorted ways, and the measurement conditions often greatly differ from study to study, both of which significantly challenge interstudy comparisons and obscure how various factors make their impacts. In this work, we reanalyze the reported results in the literature according to the minimum detectable activity (MDA) defined by Currie and investigate the effects of key elements therein. Firstly, we focus on the reported background count rates and analyze their dependence on detector’s energy resolution and active area. Secondly, we turn to the reported calibration factors and conduct analysis in the same manner. Thirdly, we calculate MDA for each study and monitor its dependence on the active area of detector and measurement duration. In the limit of the largest achievable active area (∼75000 mm2), it is found that the asymptotic MDA is approximately 6 (4) Bq and 15 (11) Bq under 30 (60) min measurement using NaI-CsI scintillator and HPGe semiconductor detectors, respectively. Finally, we discuss these asymptotic MDA in the context of estimated Pb-210 activity in the skull resulted from a hypothetical history of radon exposure.

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